Google Testing AdSense Fonts?

As I was checking my Gmail this morning, I noticed that the AdSense ads showed up in a smaller font than normal:


Usually, the ads are in the same font size as the "Seattle, WA" font above the ads. And usually there are about half as many ads as I saw this morning.

Is this just a routine Google test? Or is the big G trying to find a way to eke out every penny of AdSense revenue this holiday season?? I wonder...